A glass given an ultraviolet-light-shielding function is used as a glass plate for buildings, a glass plate for vehicles, and a glass plate for solar cell modules and the like in order to protect a person or an object inside against damage from the ultraviolet light. As an example of such an ultraviolet-light-shielding glass, Patent Document 1 describes an ultraviolet-shielding-glass formed by layering a ZnO—SiO2 thin film, and a TiO2—SiO2 thin film or ZrO2—SiO2 thin film on a surface of a glass substrate in a coating manner.
As a technique of shielding ultraviolet light and also effectively utilizing the energy of the ultraviolet light, Patent Document 2 describes that cerium ions having a valence of three are included in a glass substrate of a photovoltaic module, as a substance to convert the ultraviolet light into visible light.